Device for vaporizing a fluid, particularly a fogging fluid or extinguishing fluid

ABSTRACT

The invention relates to a device for vaporizing a fluid, particularly a fogging fluid or extinguishing fluid, comprising a vaporizing body that is provided with at least one vaporizing channel. The fluid or an already partially vaporized fluid in the form of wet vapor or a mixture thereof can be fed to the vaporizing channel via a feed opening. The fluid that is vaporized in an essentially complete manner escapes out of a discharge opening, whereby the cross-section of the vaporizer channel is designed so that is enlarges from the feed opening toward the discharge opening.

The invention relates to a device for vaporizing a fluid, especially anebulizing or extinguishing fluid, with the features of the generic partof claim 1.

Devices for vaporizing a fluid can be used, e.g., to cloud a space,e.g., the cabin of a motor vehicle. Such a device can serve as theftprotection, since the mist produced when an unauthorized person attemptsto gain access to the vehicle or attempts to move it hinders theunauthorized person in his actions and/or generates indications of anunauthorized use of the vehicle that can be clearly recognized from theoutside. In addition, a device for vaporizing a fluid can, whenappropriately designed, also be used to extinguish a fire.

It is necessary for both uses that the vaporizing device supply asufficient amount of vapor in a relatively short time. Moreover, it isdesirable in many instances that the vaporizing device have a smallsize.

DE 196 42 574 A1 discloses a nebulizing cartridge in which aheating-body housing filled with a thermite mixture is inserted into thehousing of the nebulizing cartridge. The heating-body housing has ribson its outer circumference in order to make possible the best possiblethermal transition from the heating-body housing to the fluid to bevaporized, which is present in the substantially annular space betweenthe inner wall of the cartridge housing and the outer wall of theheating-body housing. Several outlet openings are provided in the coverof the cup-shaped cartridge housing, through which the generated vaporexits after activation of the thermite mixture. In addition, DE 196 42574 A1 describes an embodiment in which the heating-body housing issurrounded by a vaporizer conduit that can be formed by a tube helicallysurrounding the heating-body housing, or that can be cast into a jacketsurrounding the heating-body housing.

EP 0878 242 A2 describes similar devices for vaporizing and/ornebulizing a liquid. For example, FIGS. 8-10 show an embodiment in whichthe outer wall of a heating-body housing filled with a thermite mixturehas one or more grooves that form one-or more vaporizer conduits bycontacting the inner wall of an annular cooling body. These vaporizerconduits have the purpose of further drying the vaporized fluid that issupplied to the vaporizer conduits from an annular chamber surroundingthe cooling body, in which chamber the generation of a wet vapor takesplace. Supply of the wet vapor to the vaporizing conduits takes placevia a throttle formed by a bore with a rather small diameter. Thislimits the mass flow at the entrance of a vaporizer conduit. This isnecessary in order to avoid a compression shock that might be produced,based on the constant cross section of the vaporizer conduit over itslength, as a consequence of the further heating and therewith of thevolumetric expansion of the vapor to be dried if the vapor to be driedor the fluid to be vaporized were supplied to the vaporizer conduit viaits completely open cross section.

The invention has the basic problem, starting from this state of theart, of creating a device for vaporizing a fluid, in particular anebulizing fluid, that has a small size and at the same time makes itpossible to produce vapor with a large mass flow.

The invention solves this problem with the features of claim 1.

The invention starts with the recognition that a vaporizer conduit witha cross section that widens out from the supply opening in the directionof the exit opening achieves a utilization of the vaporizer crosssection that is substantially improved by comparison to vaporizerconduits with a constant cross section. This takes into account thegreater space requirement of the hot vapor that is becoming hotter.Thus, a reduction of the space requirement results by comparison toknown devices with a constant conduit cross section, as a consequence ofwhich smaller structural forms are possible.

In one embodiment of the invention the vaporizer conduit can haveseveral zones with a constant cross section for each wherein the crosssection of the zones increases in the direction of the exit opening.Such an embodiment does not assure an optimal utilization of the conduitcross section, but does make possible a very simple manufacture of thevaporizer body.

In another embodiment the vaporizer conduit has one or more areas with acontinuously increasing cross section. This results, by comparison tothe previously described embodiment, in a further improved utilizationof the conduit cross section and of the surface of the vaporizer conduitas regards the thermal transfer to the fluid to be vaporized and to thewet vapor to be dried or vaporized more completely.

In one embodiment of the invention the vaporizer body comprises a firstelement in whose inner or outer wall at least one groove-shaped recessis provided for forming at least one vaporizer conduit. The firstelement can be designed as a hollow element, preferably as a hollowcylinder. At least one vaporizer conduit with a predetermined length isformed in combination with a second element comprising a wallcooperating with the inner wall or the outer wall of the first elementsuch that a seal of the one or more groove-shaped recesses is formed. Ofcourse, groove-shaped recesses can also be provided in a given wall ofthe second element that form, together with the recesses in thecorresponding wall of the first element, a vaporizer conduit withcorrespondingly enlarged cross section. In a corresponding manner agroove-shaped recess forming a vaporizer conduit can also be providedonly in the particular wall of the second element.

In a further embodiment of the invention the cooperating walls of thefirst and of the second element can form a predetermined small anglewith the longitudinal axis, preferably in a range of 0.1 to 5°, so thatso that when the two elements are inserted into one another high radialforces effecting sealing of the conduit result even at relatively lowaxial forces, and good thermal transmission is reliably achieved withoutsoldering or welding.

In one embodiment of the device of the invention a heat-producing and/orheat-storing device is provided directly bordering on the inner or outerwall of the vaporizer body, creating a good heat-conducting transitionfrom the heat-producing and/or heat-storing device to the vaporizerbody. The heat-producing and/or heat-storing device can be designed as apyrotechnic heating device comprising a pyrotechnic heating mixture or athermite mixture. In this manner a controllably activatable device forvaporizing the fluid can be realized that produces a large amount ofvapor in a short time.

In another embodiment of the invention the heat-producing and/orheat-storing device can comprise a heat-storage medium, e.g., a salinesolution, oil or, e.g., a metallic heat-storage medium that is solid atroom temperature and can be volatilized by supplied energy. Theheat-storage medium can be supplied with thermal energy from an externaldevice. If a metallic heat-storage medium is selected, e.g., aluminum,brass or a solder, a maintenance temperature can be achieved at thedesired vaporization temperature by using a suitable alloy.

According to an embodiment of the invention the vaporizer body and theheat-producing and/or heat-storing device can be designed as anintegrated cartridge, and at the same time the vaporizer body isdesigned as a container for receiving the heat-producing and/orheat-storage medium. This results in a simple and economical manufactureof the device.

Other embodiments result from the subclaims.

The invention is described in the following using as examplesembodiments shown in the drawings.

FIG. 1 shows a first embodiment of a device for vaporizing a fluid, inlongitudinal section.

FIG. 2 shows another embodiment of the invention for vaporizing a fluidas an integrated cartridge.

FIG. 3 shows an oblique view of a tubular element for realizing avaporizer body according to FIG. 2.

FIG. 4 shows another embodiment of an element for realizing a vaporizerbody with a vaporizer conduit that widens out continuously.

Device 1 for vaporizing fluid 3, shown in FIG. 1, comprises housing 5consisting of hollow cylindrical wall part 7, bottom part 9 and coverpart 11. Wall part 7 can consist, as FIG. 1 shows, of inner part 7 a,e.g., of high-grads steel, and outer part 7 b connected to it andconsisting, e.g., of a short-term temperature-stable plastic. Wall part7 can be adhered to or pressed against bottom part 9, which can alsoconsist of plastic. For this purpose, bottom part 9 can comprise annularelevation 9 a. In addition, sealing element 13, e.g., in the form of anO-ring, can be provided for creating a seal between the outer wall ofannular elevation 9 a and the inner wall of wall part 7. A threadedcoupling, shown in dotted lines in FIG. 1, can also be provided (ifnecessary, in addition) for connecting wall part 7 to bottom part 9.Cover part 11 can be connected in the same manner as bottom part 9 towall part 7. Cover part 11 can be designed substantially like bottompart 9 and comprise a circumferential annular elevation 11 a. Anothersealing element 15, e.g., in the form of an O-ring, can be provided forcreating a seal between the outer wall of annular elevation 11 a and theinner wall of wall part 7. Also, wall part 7 and bottom part 9 or wallpart 7 and cover part 11 can be designed as one piece.

Heating cartridge 17 is provided in the interior of housing 5 andcomprises a first, preferably substantially hollow-cylindrical, element19 comprising respective groove-shaped recesses 21 and 23 in its innerand in its outer wall. The first element 19 consists of a material thatis a good heat conductor, and is sufficiently temperature-stable, e.g.,aluminum.

A second element 25 that can be designed, e.g., as an aluminum tube, isprovided on the outer wall of first element 19. The inside diameter ofaluminum tube 25 is selected such that it substantially matches theoutside diameter of first element 19, and that a sufficient sealingaction results between the two parts. A sealed vaporizer conduit 27 isproduced in this manner.

A third, cup-shaped element 29 whose outside diameter substantiallymatches the inside diameter of first element 19 is provided inside firstelement 19. This achieves sealing of groove-shaped recess 21 when thethird element is set into the first element, so that another vaporizerconduit 31 is formed in this manner.

As FIG. 1 shows, the outer wall of the third cup-shaped part 29 in FIG.1 can have an upwardly decreasing diameter. In other words, the outerwall of third element 29 corresponds to the shape of an upwardlytapering conical section. In a corresponding manner the inner wall offirst element 19 is designed such that the inside diameter increasestowards the bottom, as FIG. 1 shows. Thus, the tangents to the innerwall of first element 19 and to the outer wall of third element 29 thathave no radial component form a relatively small angle with axis A ofheating cartridge 17 and of device 1 that is preferably in a range of0.1° to 5°. In this way, high radially acting sealing forces between thefacing surfaces can be produced when third, cup-shaped element 29 isinserted into first element 19 even with the production of a slightaxial insertion force.

Of course, second element 25 can be connected in the same manner to thefirst element. However, the connection of these two elements can also beeffected by adhesion, shrinking-on, soldering, welding, or the like inthe framework of a solid, non-separable connection. The advantage of thepreviously described connection of first part 19 to third part 29 viaappropriately inclined surfaces is that third element 29 can bedetachably connected to first element 19. If third element 29 serves, asshown in FIG. 1, to receive a pyrotechnic material or a thermite mixture33, third element 29 can thus be simply and economically replaced by anew element after onetime actuation of material 33 producing thermalenergy.

Heating cartridge 17 is fixed in housing 5 by being held by its lowerend in annular elevation 9 a of bottom part 9. Heating cartridge 17 isfixed in its upper area in the same manner by cover part 11, wherein therespective upper areas of second element 25 and of third element 29 areheld in corresponding recesses or their inner walls in cover part 111.Other sealing elements 35, 37, 39 can be provided for a seal between theinner wall of annular elevation 9 a or annular elevation 11 a and theouter wall of second element 25 as well as between the inner wall of areceiving socket for third element 29 in cover part 11 and the outerwall of third element 29.

Another sealing element 41 shaped like a ring disk can be providedbetween the upper end faces of first element 19 and second element 25and the upper inside wall of cover part 11. The upper side wall of coverpart 11 loads the first and the second element 19, 25 of heatingcartridge 17 in the axial direction via this sealing element 41 so thatthe desired radial sealing forces are produced between the outer wall ofthird element 29 and the inner wall of first element 19. The receivingsocket for the upper area of third element 29 in cover part 11 isdesigned such that a loading of the upper end face wall of third element29 only occurs after first element 19 has been pushed far enough ontothird element 29 that sufficiently high radial sealing forces areproduced.

Such a securing of first element 19 and of third element 29 can ofcourse also be achieved if third element 29, viewed in the axialdirection, is designed to be inversely conical. In this instance firstelement 19 can rest on bottom part 9 and third element 29 can be pressedinto first element 19 by cover part 11.

Furthermore, electrode passage element 43 is provided in cover part 11through which electrodes (not shown) are run into the interior of thirdelement 29, these electrodes extending far enough into the area filledwith the pyrotechnic or thermite mixture 33 that activation or ignitionof the material is assured. For this purpose the electrodes can beconnected via a heating wire or heated filament extending into material33 so that when current flows through the electrodes the heating wire isheated until it glows and ignites pyrotechnic or thermite mixture 33.Instead of the heating wire or heated filament an element can also beused that generates a plasma when current flows through. This issuitable, e.g., to ignite a thermite mixture. The inner space of thirdelement 29 is as a rule not completely filled with material 33. In orderto protect cover part 11 from the combustion products the partial areaof the inner space is delimited by disk element 45. Element 45 can befixed, e.g., by being pressed in, adhered in or snapped into the innerwall of thlrd element 29. The disk element preferably consists of steelor copper.

The lower front side of third element 29 is designed such that the areaadjacent to axis A projects beyond the lateral areas (downward in FIG.1). Accordingly, annular space 47 remains free when third element 29 andheating cartridge 17 are inserted into housing 5, this annular spaceestablishing a communication between vaporizer conduits 27, 31. For thispurpose, groove-shaped recesses 27, 31 are designed such thatappropriate openings empty into annular space 47 on the lower front sideof first element 19, and both recesses simply end at the lower end ofelement 19.

As FIG. 1 shows, at least one supply opening 49 that is closed byelement 51 in a membrane-like manner is provided in second element 25 inthe upper area of annular recess 23 and of vaporizer conduit 27.

In this manner, after the activation of material 33 producing thermalenergy in the interior of third element 29 of heating cartridge 17, thethermal energy produced is transmitted via the wall of third element 29to first element 19 and from the latter via second element 25 to fluid53 to be vaporized that was received in the annular space between theinner wall of wall element 7 and the outer wall of second element 25 ofheating cartridge 17 in housing 5.

After the beginning of supply of the thermal energy to fluid 53, thefluid is at first heated or vaporized until the pressure exceeds apredetermined value that causes closure element 51 to burst. Fluid 53 ora suitable wet vapor or a mixture thereof subsequently enters vaporizerconduit 27 via supply opening 49. During its passage through vaporizerconduit 27 the fluid is heated further or vaporized further. After ithas passed through helical vaporizer conduit 27 the fluid/vapor mixtureor a still relatively wet vapor enters into the lower opening ofvaporizer conduit 31.

It should be mentioned at this point that a sealing material or thermalinsulation material 55, e.g. in the form of a sealing disk, can ofcourse be provided between the bottom-side end wall of third element 29and the surface of bottom part 9 facing it.

To the extent that vaporizer conduit 27 has a constant conduit crosssection between supply opening 49 and the bottom-side exit opening,vaporizer conduit 31 is designed such that its conduit cross sectionexpands continuously in the direction from its bottom-side supplyopening to the exit opening connected to exit opening 57 in cover part11. In this way, as the vaporization state of fluid 53 becomes more andmore complete, its increased volumetric requirement is taken intoaccount. A compression shock that might lead to a “blockage” ofvaporizer conduit 31 is reliably avoided in this manner. The crosssection of the conduit is preferably selected such that at each point ofconduit 31 (viewed over its length) the cross section of the conduit ina differential element of length is selected such that the differentialvolume is adapted to the volume of the vaporized fluid contained in itat the prevailing temperature and prevailing pressure.

Of course, vaporizer conduit 27 could also already be designed with awidening cross section.

The formation of a vaporizer conduit in the inner wall and outer wall offirst element 19 results in the advantage of a sufficiently longvaporizer conduit (with a correspondingly large surface for thetransmission of heat) with a small overall height at the same time.Furthermore, supply opening 49 can be selected in an area located abovethe liquid level in the case of an incomplete filling of the annularspace with fluid 53 to be vaporized. This applies at least when device 1shown in FIG. 1 is used in the upright position. The direct entrance ofnon-vaporized fluid 53 into vaporizer conduit 27 is avoided in thismanner.

FIG. 2 shows another embodiment of a device for vaporizing a fluid thatis designed essentially only as a heating cartridge similar to heatingcartridge 17 of FIG. 1. Device 100 shown in FIG. 2 has a housing 102which comprises wall part 104, cup-shaped part 106 engaging with it, andcover part 108. Cup-shaped part 106 comprises helical, groove-shapedrecess 110 in its outer wall, this recess being divided along its pathinto two areas with different cross sections.

The outer wall of cup-shaped part 106 cooperates for its part in asealing manner with the inner wall of wall part 104 pushed onto it, sothat tight vaporizer conduit 112 is produced that is designed inaccordance with the path of groove-shaped recess 110. Radial supplyopening 114 is designed in the bottom area of cup-shaped part 106, thisopening communicating with vaporizer conduit 112 or its first sectionwith a smaller cross section. In the upper area of the wall ofcup-shaped part 106, vaporizer conduit 112 opens out into annular space116 that communicates with several exit openings 118 formed in coverpart 108. Cover part 108 is connected in a sealing manner to wall part104 and cup-shaped part 106. In order to create a seal, sealing elements120, 122 can be provided between an outer wall of cover part 108 and theinner wall of wall part 104 or between an outer wall of an area of wallpart 104 engaging into cup-shaped part 106 and between the inner wall ofcup-shaped part 106. In the same manner, wall part 104 can be connectedin its lower area by another sealing element 124, provided between theinner wall of wall part 104 and between the outer wall of cup-shapedpart 106, in a sealing manner to cup-shaped part 106. Just as in theembodiment according to FIG. 1, a part of the inner space of cup-shapedpart 106 delimited by protective element 126 is filled with anactivatable, heat-producing material 35, e.g., a pyrotechnic mixture orthermite mixture. Again, two electrodes 128 (sealed in a manner that isnot shown) are run through cover part 108 and connected to activatingdevice 130 for activating material 35 that produces thermal energy. Inthe simplest case, activating device 130 can be a heating wire.

Of course, device 100 shown in FIG. 2 can also be used as a heatingcartridge in a device similar to device 1 in FIG. 1. For this purpose,e.g., supply opening 114 could be appropriately blocked so that thefluid to be vaporized does not enter into vaporizer conduit 112 until apredetermined pressure has been exceeded after bursting of the closureelement. However, the fluid to be vaporized can be supplied to supplyopening 114 with the appropriate pressure in any other manner desired,e.g., from an external storage container.

Conversely, the inner wall of third element 29 of the embodiment in FIG.1 can of course also be provided with structure 132 shown in FIG. 2 thatenlarges the surface of the element concerned for improving the heattransfer. For example, structure 132 can comprise ribs in the inner wallof concerned element 29 or 106.

FIG. 3 shows an oblique view of cup-shaped element 106 in which the twoareas of annular groove 110 that have different cross sections anddefine vaporizer conduit 112, can be better recognized. The lower area,shown in FIG. 3, starts from annular recess 134 communicating, as FIG. 2shows, with radial supply opening 114. The connection of the first areaof groove-shaped recess 110 with a smaller cross section to the secondarea with a larger cross section takes place for its part via annulararea 136.

Annular areas 134, 136 are essentially provided in order to facilitatethe manufacturing process.

FIG. 4 shows another embodiment of a cup-shaped element 106 in which,however, annular recess 110 is designed with a continuously increasingcross section. This variant naturally represents, from the physicalstandpoint, a better selection since the cross section of the vaporizerconduit being produced can be adapted at every point of its (helical)length to the particular differential volume of the vapor.

In conclusion, it is pointed out that all features described above onlyin combination with one or the other embodiment can of course also beused, to the extent feasible, with the other embodiment.

In both instances, instead of a heat-producing material such as apyrotechnic mixture or thermite mixture, a purely heat-retainingmaterial (or also a combination of both possibilities) can be used. Inthe case of a purely heat-retaining material, it is necessary to supplyexternal energy. For example, a heating device could be provided in theinterior or also externally that introduces thermal energy into theheat-retaining material.

1. A device for vaporizing a fluid, especially a nebulizing orextinguishing fluid, a) with a vaporizer body in which at least onevaporizer conduit is formed which can be supplied via a supply openingwith the fluid, or an already partially vaporized fluid in the form ofwet vapor, or a mixture of both, and wherein the substantiallycompletely vaporized fluid escapes from an exit opening, characterizedin that b) the cross section of the vaporizer conduit increases from thesupply opening in the direction of the exit opening.
 2. The deviceaccording to claim 1, characterized in that the vaporizer conduitcomprises several areas with a constant cross section and that the crosssection of the areas increases in the direction of the exit opening. 3.The device according to claim 1 or 2, characterized in that thevaporizer conduit comprises one or more areas with a continuouslyincreasing cross section.
 4. The device according to one of thepreceding claims, characterized in that the vaporizer conduit comprisesa first element in whose inrer and/or outer wall at least onegroove-shaped recess is provided for forming one or more vaporizerconduits.
 5. The device according to claim 4, characterized in that thefirst element is designed as a hollow element, preferably as a hollowcylinder.
 6. The device according to claim 4 or 5, characterized in thatthe vaporizer conduit comprises at least one second element comprising awall cooperating with the inner wall or the outer wall of the firsthollow element such that it seals the one or more groove-shaped recessesin order to form the one or more vaporizer conduits.
 7. The deviceaccording to claim 6, characterized in that the cooperating walls of thefirst and of the second element form a predetermined small angle withthe longitudinal axis, preferably in a range of 0.1° to 5°.
 8. Thedevice according to one of the preceding claims, characterized in that aheat-producing and/or heat-storing device is provided directly borderingon the inner or outer wall of the vaporizer body, creating a goodheat-conducting transition from the heat-producing and/or heat-storingdevice to the vaporizer body.
 9. The device according to claim 8,characterized in that the heat-producing and/or heat-storing device isdesigned as a pyrotechnic heating device comprising a pyrotechnicheating mixture or a thermite mixture.
 10. The device according to claim8, characterized in that the heat-producing and/or heat-storing devicecomprises a heat-storage medium, preferably a saline solution, oil ore.g., a metallic heat-storage medium that is solid at room temperatureand can be volatilized by supplied energy.
 11. The device according toone of claims 8 to 10, characterized in that the heat-producing and/orheat-storing device is arranged inside the vaporizer conduit.
 12. Thedevice according to one of claims 8 to 11 characterized in that thevaporizer conduit and the heat-producing and/or heat-storing device aredesigned as an integrated cartridge, and that the vaporizer body isdesigned at the same time as a container for receiving theheat-producing and/or heat-storage medium.